diff --git a/Helios/Source/ConfiguratorService.cs b/Helios/Source/ConfiguratorService.cs
index fa2d06a6d691abb5bd476051bd05cbcb0b16e23e..96c2206d618e81ef94e032568a7fe927020f51d2 100644
--- a/Helios/Source/ConfiguratorService.cs
+++ b/Helios/Source/ConfiguratorService.cs
@@ -41,7 +41,10 @@ namespace Helios.Source
 					result.ExceedsMaximumPower = ExceedsPowerLimit(input.MaximumPower, result.PowerGeneratedWinter);
 					result.WithinBudget = WithinBudget(input.Budget, result.InstallationCost);
 
-					results.Add(result);
+					if (result.RoofAngle != 0)
+					{
+						results.Add(result);
+					}
 				}
 			}